1. Technical Field
The disclosure relates in general to a key activity detection system and a method thereof.
2. Background
Currently, there are many ways for detecting whether multiple keys are pressed/released. Let the computer keyboard be taken for example. A computer keyboard has many independent driving lines and sensing lines. Which computer key(s) is/are pressed/released can be identified by sequentially scanning the driving lines. However, this method is applicable to the computer keyboard with large-sized printed circuit board.
Let the human machine interface be taken for example. For example, the DVD drive or the DVD player equipped with push buttons detects whether the button (such as disc ejection button) is pressed, so that the DVD drive or the DVD player performs corresponding mechanical operation (such as to eject the disc). Currently, to detect whether a key/button is pressed/released in a human machine interface system can be implemented by an analog-to-digital converter (ADC). Since the ADC is an analog circuit, once the chip manufacturer or the manufacturing process changes, the adaptation of the ADC needs to be checked again. In some cases, a re-designed new ADC may be needed, which raises a big waste of time and resources. Further, the ADC needs to cooperate with analog pins, which can only support fixed functions and cannot be adapted to fit the needs of design change.
Therefore, it is a prominent task for the industries to provide a key activity detection system which resolves the weakness of the currently available technology.